Not Your Parents’ Drug: Marijuana Potency Reaches All-Time High

By Hugh C. McBride

The memory of their own youthful experimentation with marijuana has led some parents to believe their children face little or no risk from this “benign” drug. But a recent report by the White House Office of National Drug Control Policy indicates that the marijuana being smoked by today’s teenagers is significantly more potent than that used by previous generations.

The government report, which was based on information provided by the University of Mississippi’s Potency Monitoring Project, indicates that the marijuana that was analyzed in 2007 had a THC level of 9.6 percent – the highest level since analysts began tracking this data in 1976. The previous potency peak was 8.75 percent, which was recorded in 2006.

THC, which is short for tetrahydrocannabinol, is the primary psychoactive substance in the cannabis plant, from which marijuana, sinsemilla, and hashish are derived.

In a June 12, 2008 press release issued by the ONDCP, the agency’s director, John Walters, said the potency report reaffirms the federal government’s position on the dangers of marijuana. “Baby boomer parents who still think marijuana is a harmless substance need to look at the facts,” Walters said. “Marijuana potency has grown steeply over the past decade, with serious implications in particular for young people.”

The ONDCP release also quotes Dr. Nora Volkow, the director of the National Institute on Drug Abuse, who notes that the heightened potency of today’s marijuana may increase the toxic effects of the drug. “Particularly worrisome is the possibility that the more potent THC might be more effective at triggering the changes in the brain that can lead to addiction,” Volkow said. “However, more research is needed to establish this link between higher THC potency and higher addiction risk.”

About the Study
The Potency Monitoring Project, which is funded by the National Institute on Drug Abuse, studies samples of drugs that have been confiscated by law enforcement personnel. In the 32 years that the project has been in operation, its researchers have analyzed more than 62,000 marijuana samples and more than 1,300 hashish samples.

The average THC content in samples studied by PMP researchers hovered between 3 and 4 percent from 1983 to 1995, then began a fairly steady incline. The annual average exceeded 4 percent for the first time in 1996, and crossed the 6 percent threshold in 2001. It hit 7 percent in 2002, and registered above 8 percent for the first time in 2004.

The National Drug Intelligence Center attributes the recent potency spikes to improvements in cannabis cultivation methods by individual growers, criminal groups, and drug trafficking organizations. In the “Marijuana” section of the NDIC’s National Drug Threat Assessment 2008, the agency noted that “indoor cannabis cultivation is increasing in some areas of the country as growers attempt to avoid outdoor eradication and attain higher profits through production of indoor-grown, high-potency marijuana.”

The proficiency of these high-potency cultivation efforts is reflected in the Potency Monitoring Project’s most recent report, which noted that the highest THC level found in a single sample in 2007 exceeded 37 percent.

The Dangers of High-Potency Marijuana
Though most experts agree that the marijuana available in the United States today is stronger than ever, they disagree on what effect this record potency will have on the estimated 14.8 million Americans who use the drug.

The National Institute on Drug Abuse website lists “distorted perceptions, impaired coordination, difficulty in thinking and problem solving, and problems with learning and memory” among the effects of marijuana intoxication. The site also references research that has associated chronic marijuana use with increases in anxiety, depression, suicidal thoughts, and schizophrenia.

In an Aug. 19, 2003 interview with The New York Times, Nora Volkow conceded that the link between marijuana use and permanent psychological impairment has not been established beyond a doubt, but she advocated continued research to prove what initial studies have indicated.

“I’ve used imaging, and clearly we have shown that marijuana abusers have changes in certain areas of the brain involved with memory and motor coordination,” Volkow told Times reporter Mary Duenwald. “If people are smoking marijuana, they should know what marijuana is doing to their brain. We need to do the work.”

In addition to that lab work, the United States’ “drug czar” believes it is essential to continue to spread the word that marijuana at any level of potency puts young users at risk. “Marijuana is not the answer,” John Waters said in a May 9, 2008 press release. “Too many young people are making a bad situation worse by using marijuana.”